Tissue processors can be operated with varying levels of automation to process human or animal tissue specimens for histology or pathology uses. Various types of chemical reagents can be used at various stages of tissue processing and various systems have been developed for delivering reagents to microscope slides containing specimens. Examples of known reagent delivery systems include small quantity release dispensers, technicians manually pouring reagents into reagent vats, and bulk containers connected with a specimen processor via tubing.
There are various disadvantages of known systems. For example, a technician manually pouring reagents into, or draining, reagent vats suffers the disadvantages of being time consuming and requiring pouring accuracy which decreases the overall efficiency of the tissue processing system. Another disadvantage is that manually pouring and draining reagents can be sloppy, requiring clean-up of spills and consequential instrument down-time. A further disadvantage is that selecting the correct reagent requires operator attention and accuracy and there is an increased possibility of reagent application errors, which decreases test accuracy and operational efficiency.
In the previously known automated systems, there are also disadvantages. In those systems, reagents are selected and administered to slides during processing, frequently via gravity promoted dispensing from above. Such delivery systems require specialized equipment for reagent delivery such as specialized reagent dispensers, drivers or automated pipetting systems. Such systems suffer various drawbacks such as the amount of effort required to set up and dispense the reagents, the possibilities of evaporation during processing or contamination and difficulties in handling minute quantities of large numbers of reagents.